Electronic voting techniques are often used to collect public opinion from an audience during an event. For example, members of an audience may be asked to submit their individual opinions via a communications or computer network during a televised entertainment event or during a political event. The individual opinions may then be analyzed to determine the aggregate opinions of the audience.
Frequently, voting is triggered by a live, broadcast announcement. A televised talent show may ask the audience to vote on a preferred performer, providing one or more toll-free (8YY) numbers for audience members to call to place a vote. Vast numbers of votes are therefore placed nearly simultaneously.
The callers may each use the one or more toll-free 8YY numbers (such as a number with an 800 area code) for voting. In one scenario, a single 8YY number per candidate is assigned. In that case, a call to a number indicates a vote for a candidate. A voting caller is played a courtesy announcement affirming receipt of the vote.
In another scenario, a single 8YY number is used for the entire election. In that embodiment, an interactive voice response unit (IVR) is used to prompt the caller to vote for the desired candidate by, for example, pressing designated keys on a touchtone phone.
In a typical scenario, a media company interested in staging such a television viewer-based voting event contracts with a network provider to provide one or more 8YY numbers that audience members can call from their residential phones to place a vote.
An example of a prior art system 100 is shown in FIG. 1. Calls from each dialed 8YY number (e.g., 120, 121) used during the mass calling event are routed by a local exchange carrier (e.g., 110, 111) to 4ESS switches such as switch 112, to a single pair of network control points 130, 140 (NCPs) to receive call instructions. In one present implementation of the system, there are 140 such 4ESS switches in the system.
Based on responses from the NCPs 130, 140 received at the 4ESS switch 112, calls are then routed to an announcement resource 116 at the originating 4ESS switch to receive a courtesy response announcement. The announcement resource 116 includes S and D set announcement frames, both of which are utilized in servicing the mass calling event.
Call capacity of an architecture such as that shown in FIG. 1, including 140 4ESS switches, is approximately 840K calls per hour. Call throughput is limited by the fact that all calls are routed to the single NCP pair 130, 140 during call processing, and announcement resources are not equally distributed between D and S sets. The inventors have found that, during a mass calling event, the single NCP pair, together with unbalanced use of the S and D announcement resources, creates a bottleneck.
Several improvements have been implemented to increase throughput in the above-described system. Improvements to three network elements within the AT&T Switched Network have been implemented: the 4ESS switch, Advance 800 Network Control Point, and the D and S set ISAIC announcement frames.
An improved high capacity network architecture 200 for 8YY mass calling events is shown in FIG. 2. The high capacity A800 Service architecture 200 utilizes several elements to increase call completions during a mass calling event. First, the architecture includes dedicated mapping of traffic from a 4ESS switch such as switch 230 to an NCP pair such as pair 255, 265. The subsystems 280, 290 are similarly mapped from 4ESS switches to dedicated NCP pairs. Sixteen pairs of NCPs (three of which are shown in FIG. 2) are utilized in one exemplary system. Originating 8YY traffic is thereby evenly distributed to those NCP pairs.
The capability to evenly distribute 8YY traffic from originating switch to Network Control Point is provided by a 10 digit dialed number translation table (not shown) within each 4E switch 230. That table associates the dialed 8YY number to a network address (point code). The address is used to route 8YY calls to a Network Control Point for further call processing. The table allows network engineers to match call volumes of each dialed number and originating 4E to the corresponding capacity of a Network Control Point in the network. The translation table containing the switch-to-NCP relationship is produced and provisioned into the network prior to the start of each unique mass calling event.
Another system enhancement is the replication of the account record within each A800 NCP database 250, 260 in the network. All NCPs are provisioned with the customer's account record so that each call is processed using the same features and call logic regardless of which NCP is used to process the call. 8YY calls are received at one of the 16 pairs of Advanced 8YY Network Control Point (NCP-A800) databases. The NCP processes queries received from the switch and responds back with a reply message. The switch uses the announcement information in the reply to redirect the call to a courtesy response announcement.
Yet another enhancement is the use of the preexisting call allocator feature to distribute announcement traffic between D and S set announcement resources within the announcement frame 240. The call allocator feature within the customer's routing plan is used to load share traffic between the two different announcement sets within the AT&T network.
When the NCP reply message is received by the originating 4E switch the call is directed to the announcement resource 240 within the switch and the caller is played an announcement acknowledging the receipt of the call. In order to evenly distribute calls between the S and D set announcement resources, the call allocator feature is used in the customer record to alternate calls between the two announcement sets. Traffic to these announcement sets will route to two overflow options in the network before being blocked. This capability may be available using either the standard architecture of FIG. 1 or the mass calling event architecture of FIG. 2. Once the caller hears the short courtesy response announcement the call is ended. Call completion data is collected and forwarded to the customer after the event.
Together, the above-described improvements have increased the throughput of the standard AT&T Advance 8YY network architecture from a maximum of 8 million calls to approximately 30 million call attempts using that network design.
An existing architecture 300 used in current network edge switch systems is shown in FIG. 3. Calls received by network edge switches (NESVs) 310 are referred to segmentation databases such as SD 320. The network edge switch (NESV) 310 uses a “round robin” distribution identify an SD for a particular call; i.e., sequential received calls are assigned to SDs in a repeating sequence.
All SDs 320 are identical, containing a service processor index (SPI) that identifies a particular NCP 330 for routing calls associated with a particular 8YY customer. Therefore, during a mass calling event, all calls for a given 8YY number account will be directed to the same NCP 330. The NCP may be a bottleneck during a high volume event.
Other systems have been proposed for overcoming the congestion problem triggered by a telephone voting event. For example, U.S. Pat. No. 6,768,895 discloses a mobile telephone voting system wherein a polling server authorizes only a predetermined percentage of incoming voting calls. The percentage is increased or decreased in subsequent rounds based on a statistical analysis of the previous results. In that way, the polling server may be scaled down and network congestion is reduced.
While the above improvements have been effective, there remains a need for a telephonic voting system that may be used to record opinion during a national or widely-viewed event, while further minimizing network congestion caused by the voting calls.